--参数列表
local voucherId = ARGV[1]
local userId = ARGV[2]
local orderId = ARGV[3]
local stockKey = 'seckill:stock:' .. voucherId
local orderKey = 'seckill:order:'.. voucherId
if(tonumber(redis.call('get', stockKey)) <= 0) then
return 1
end
if(redis.call('sismember', orderKey, userId) == 1) then
return 2
end
redis.call('incrby', stockKey, -1)
redis.call('sadd', orderKey, userId)
--发送消息到消息队列，实现消息的可靠投递
redis.call('xadd', 'stream.orders', '*', 'userId', userId, 'voucherId', voucherId, 'id', orderId)
return 0
